1. Field of the Invention
The present invention relates generally to an improved switch wire connection device, and more particularly to a switch wire connection device including a restriction unit, a contact plate and a metal leaf spring assembled with each other for directly electrically connecting with a conductive wire. The restriction unit has higher rigidity and is able to help in fixing the metal leaf spring and restricting the moving path thereof.
2. Description of the Related Art
A conventional switch wire connection device is a power switch device capable of connecting circuits or conductive wires. The switch wire connection device is installed on an operation panel or distribution box of an electronic or electrical apparatus for connecting the wiring circuits. The switch wire connection device has an insulation case (generally made of plastic material) and a conductive component enclosed in the insulation case and a screw for locking the wiring circuits or conductive wires of the electronic or electrical apparatus. By means of operating a switch pushbutton, the conductive component is controlled to electrically contact or separate from the wiring circuits or the conductive wires so as to close the circuit to power on the electronic or electrical apparatus or open the circuit to power off the electronic or electrical apparatus.
With respect to operation, use and structural design of the switch wire connection device, the insulation case is formed with wire sockets and screw locking holes in communication with each other. An operator can use a tool to drive the screw to lock a conductive wire plugged into the wire socket. In practice, the screw must be first positioned in the screw locking hole in a loosened state, permitting the conductive wire to plug into the wire socket. In the loosened state, the screw is often deflected. Under such circumstance, it is troublesome and hard for the operator to aim the tool at the screw to drive the screw for locking the conductive wire with the electrical contact (or termed electrical connection terminal).
To improve the above problem, there is a conventional switch wire connection device in which the insulation case and the electrical contact are formed with guide channels and guide ribs in cooperation with the spring. Such structure is relatively complicated so that the manufacturing cost is increased and generally the volume of the case is enlarged to avoid interference between the guide structures and the conductive component. The increase of the volume of the case is unbeneficial to the miniaturization of the switch wire connection terminal device and fails to meet the trend to miniaturize the switch wire connection terminal device.
Also, in some operation environments (such as the operation of the machine or the equipment will cause vibration), after a long term of use, the screw is apt to loosen. As a result, the conductive wire may loosen and detach from the case. Especially, when driving the screw mechanism to lock the conductive wires with the electrical contact, it is necessary to use a tool for tightening/untightening the screw. Such process is relatively troublesome. This is not what we expect.
There is another conventional switch wire connection device in which the case is designed with a specific internal structure and an α-shaped metal leaf spring is applied to the case for pressing the conductive wires instead of the screw mechanism. However, as known by those who are skilled in this field, the α-shaped metal leaf spring is manufactured by a special bending process and it is necessary to form a mouth section on the metal leaf spring for the other end of the metal leaf spring to swingably pass through the mouth section for pressing the conductive wire. The manufacturing process of the α-shaped metal leaf spring is quite troublesome and complicated. This is not what we expect.
To speak representatively, the conventional switch wire connection device has some shortcomings in structural design and operational form. To overcome the above shortcomings, it is necessary to redesign the insulation case, the conductive component, the electrical contact and the metal leaf spring and change the use form of the switch wire connection device and widen the application range thereof. For example, in the condition that the volume of the switch wire connection device is not increased, the switch wire connection device is redesigned to have a simplified structure, which is easy to manufacture and operate. In the conventional switch wire connection device, it is hard and troublesome for an operator to aim the tool at the screw to drive the screw for locking the conductive wire with the electrical contact. In addition, it is troublesome to assemble the guide channels and guide ribs of the insulation case and the electrical contact and the spring. Also, an α-shaped metal leaf spring is applied to the insulation case and the structure of the switch wire connection device is complicated. After redesigned, all the above shortcomings of the conventional switch wire connection device are overcome.
After redesigned, the switch wire connection device includes an electrical contact having a restriction unit and a contact plate. The restriction unit has a first space and a second space. At least two side by side conductive wires can be plugged into the case to be respectively held a metal leaf spring. Moreover, without using any tool, an operator can directly plug the conductive wires into the case to electrically connect with the electrical contact. The electrical contact has higher rigidity or hardness and good electrical conductivity and is able to help in fixing the metal leaf spring and restricting the moving path thereof. All these are not substantially taught, suggested or disclosed in the conventional switch wire connection devices.